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The cortical column was a hypothesis about a general organizational principle for the cortex, which turned out to be more or less false but which has lived on a

The cortical column was a hypothesis about a general organizational principle for the cortex, which turned out to be more or less false but which has lived on as a kind of “zombie science” because too many people built their careers around it and we can’t admit that it isn’t a real thing until they all retire. The thing that actually exists is “neurons above and below each other tend to respond to the same stimulus/action in the real world.” Jeff Hawkins, being a smart neuroscience-amateur, seems to have never realized that cortical columns are this nice idea that was found to be wrong a long time ago, but neuroscientists don’t say that out of politeness to the profs who built their careers on the concept. For more detail: https://pubmed.ncbi.nlm.nih.gov/15937015/ https://pubmed.ncbi.nlm.nih.gov/15937015/

iandanforth 5y ago
Disclaimer: Worked at Numenta. I think your statement could be better informed. The article you link to for example doesn't deny the common structure of cortical columns, but posits that they don't have a known function. That's kinda the point of Numenta's research. To suggest a function. And it's not that the idea of cortical columns (or more specifically minicolumns) was found to be wrong, we've gone from a simplistic explanation to a more complex one via both more careful measurement, new techniques, and cross species comparisons. I think this review is pretty good on these points: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2820381/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2820381/ There's also this idea that the neocortex is composed of 6 layers. That idea isn't totally wrong but it's required updating as we gain more information. Even the neuron hypothesis itself has had to undergo significant revision as we better understand the computational power of sub-neuron units and companion cells like astrocytes. So if you want to criticize cortical columns for being an over simplification, that's fine, but 1. we all know that and 2. simplifications are particularly useful when you need to reduce such systems to code as the OP has done.
- georgewfraser 5y ago
  Disclaimer: have personally recorded from whisker barrels, the structure that inspired Vernon Mountcastle to posit the idea of the cortical column. He’s my neuro-great-grandfather according to neurotree: https://neurotree.org/neurotree/tree.php?pid=154706&fontsize=1&pnodecount=4&cnodecount=2 https://neurotree.org/neurotree/tree.php?pid=154706&fontsize... The idea of cortical columns isn’t like the 6-layer-cortex. The cortex just isn’t organized into little column-shaped modules. It’s true that if you record two neurons right on top of each other, they’ll have a similar receptive field/preferred direction/…. BUT there is no consistent horizontal organization of neurons into columns. There’s whisker barrels, which reflect the way rat and mouse whiskers work, and there’s ocular dominance columns, which are a totally different thing at a different spatial scale. But there’s no global organizing principle that should be called “cortical columns”. It’s a lovely idea that would be great if it were true—-it would be so much easier to understand the brain if there were a common unit of organization larger than a neuron but smaller than a brain! But it’s not so.
  - igorkraw 5y ago
    Do you have any recommendations what papers/books/researcher output to read to catch up to the bleeding edge of neuroscience research ASAP?
    - trombonechamp 5y ago
      Disclaimer: georgewfraser is my academic cousin. Neuroscience research is huge and moving fast. Researchers have trouble keeping up with the bleeding edge in their sub-sub-field, let alone neuroscience as a whole. Conferences are one major way that most of us find out about new work. Pre-covid, conferences were pretty exclusive and unwelcoming to non-researchers. However, now that conferences are all online due to covid, one thing I would recommend is going through the videos of old conferences to find something you are interested in. Then you can pause the video and look up any words or concepts which are unfamiliar. It may take a while to get through a talk, but you'll learn a lot this way. For example, Neuromatch is the big "mostly computational neuroscience" online conference: https://www.youtube.com/channel/UCcBKrxkfNv04R9PXLovjf5w/videos https://www.youtube.com/channel/UCcBKrxkfNv04R9PXLovjf5w/vid... Another formerly-in-person conference is Cosyne: https://www.youtube.com/channel/UCzOTbZTHTubFNjANAR33AAg/videos https://www.youtube.com/channel/UCzOTbZTHTubFNjANAR33AAg/vid... Heck, registration for Neuromatch is cheap so you can attend this year's conference if you want to: https://conference.neuromatch.io/ https://conference.neuromatch.io/
  - HarHarVeryFunny 5y ago
    Even if there's nothing in the cortical organization itself to suggest cortical columns, is it still true that there are "cortical column sized" regions of non-overlapping sensory receptive fields in the cortex ?
  - iandanforth 5y ago
    Let's call the phenomenon you seem to dismiss as obvious and uninteresting, that neurons "right on top of each other" have similar receptive fields, 'minicolumns.' These exist consistently across the cortex. We've mapped out their shape and connections. This is what one looks like https://www.youtube.com/watch?v=jmdPOaTpZWA https://www.youtube.com/watch?v=jmdPOaTpZWA (this even links to the paper you cited but calls them 'cortical columns'). Let's call the larger column structures with significant horizontal coverage posited by Mountcastle 'hypercolumns.' As you and others have noted these seem to be limited or non-existent. As I've said thanks to updates to our technology we've refined the idea of 'cortical columns' into a class which doesn't have useful explanatory power ('hypercolumns') and one which does ('minicolumns'.) The vertical integration of processing across layers of cortex by a collection of neurons is IMO of significant interest and import. You may disagree, but please don't pretend that these structures don't exist.
- specialist 5y ago
  > ...doesn't deny the common structure of cortical columns, but posits that they don't have a known function. Listening to an interview w/ Jeff Hawkins for "A Thousand Brains", it reminded me of Lingua Ex Machina [2009]. "A neuroscientist and a linguist show how evolution could have given rise to structured language." https://mitpress.mit.edu/books/lingua-ex-machina https://mitpress.mit.edu/books/lingua-ex-machina https://www.amazon.com/Lingua-Machina-Reconciling-Darwin-Chomsky/dp/0262531984 https://www.amazon.com/Lingua-Machina-Reconciling-Darwin-Cho... I tried to dig a bit, to see if there's a connection between Jeff Hawkins and William Calvin's works. No joy. I'm probably just grasping at straws. Am just a curious layperson. It's been ages since I read On Intelligence and Lingua Ex Machina. At the time, just the notion of Darwinian processes happening within the brain rocked my world.

iandanforth 5y ago

Disclaimer: Worked at Numenta. I think your statement could be better informed. The article you link to for example doesn't deny the common structure of cortical columns, but posits that they don't have a known function. That's kinda the point of Numenta's research. To suggest a function. And it's not that the idea of cortical columns (or more specifically minicolumns) was found to be wrong, we've gone from a simplistic explanation to a more complex one via both more careful measurement, new techniques, and cross species comparisons. I think this review is pretty good on these points: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2820381/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2820381/ There's also this idea that the neocortex is composed of 6 layers. That idea isn't totally wrong but it's required updating as we gain more information. Even the neuron hypothesis itself has had to undergo significant revision as we better understand the computational power of sub-neuron units and companion cells like astrocytes. So if you want to criticize cortical columns for being an over simplification, that's fine, but 1. we all know that and 2. simplifications are particularly useful when you need to reduce such systems to code as the OP has done.

georgewfraser 5y ago
Disclaimer: have personally recorded from whisker barrels, the structure that inspired Vernon Mountcastle to posit the idea of the cortical column. He’s my neuro-great-grandfather according to neurotree: https://neurotree.org/neurotree/tree.php?pid=154706&fontsize=1&pnodecount=4&cnodecount=2 https://neurotree.org/neurotree/tree.php?pid=154706&fontsize... The idea of cortical columns isn’t like the 6-layer-cortex. The cortex just isn’t organized into little column-shaped modules. It’s true that if you record two neurons right on top of each other, they’ll have a similar receptive field/preferred direction/…. BUT there is no consistent horizontal organization of neurons into columns. There’s whisker barrels, which reflect the way rat and mouse whiskers work, and there’s ocular dominance columns, which are a totally different thing at a different spatial scale. But there’s no global organizing principle that should be called “cortical columns”. It’s a lovely idea that would be great if it were true—-it would be so much easier to understand the brain if there were a common unit of organization larger than a neuron but smaller than a brain! But it’s not so.
- igorkraw 5y ago
  Do you have any recommendations what papers/books/researcher output to read to catch up to the bleeding edge of neuroscience research ASAP?
  - trombonechamp 5y ago
    Disclaimer: georgewfraser is my academic cousin. Neuroscience research is huge and moving fast. Researchers have trouble keeping up with the bleeding edge in their sub-sub-field, let alone neuroscience as a whole. Conferences are one major way that most of us find out about new work. Pre-covid, conferences were pretty exclusive and unwelcoming to non-researchers. However, now that conferences are all online due to covid, one thing I would recommend is going through the videos of old conferences to find something you are interested in. Then you can pause the video and look up any words or concepts which are unfamiliar. It may take a while to get through a talk, but you'll learn a lot this way. For example, Neuromatch is the big "mostly computational neuroscience" online conference: https://www.youtube.com/channel/UCcBKrxkfNv04R9PXLovjf5w/videos https://www.youtube.com/channel/UCcBKrxkfNv04R9PXLovjf5w/vid... Another formerly-in-person conference is Cosyne: https://www.youtube.com/channel/UCzOTbZTHTubFNjANAR33AAg/videos https://www.youtube.com/channel/UCzOTbZTHTubFNjANAR33AAg/vid... Heck, registration for Neuromatch is cheap so you can attend this year's conference if you want to: https://conference.neuromatch.io/ https://conference.neuromatch.io/
- HarHarVeryFunny 5y ago
  Even if there's nothing in the cortical organization itself to suggest cortical columns, is it still true that there are "cortical column sized" regions of non-overlapping sensory receptive fields in the cortex ?
- iandanforth 5y ago
  Let's call the phenomenon you seem to dismiss as obvious and uninteresting, that neurons "right on top of each other" have similar receptive fields, 'minicolumns.' These exist consistently across the cortex. We've mapped out their shape and connections. This is what one looks like https://www.youtube.com/watch?v=jmdPOaTpZWA https://www.youtube.com/watch?v=jmdPOaTpZWA (this even links to the paper you cited but calls them 'cortical columns'). Let's call the larger column structures with significant horizontal coverage posited by Mountcastle 'hypercolumns.' As you and others have noted these seem to be limited or non-existent. As I've said thanks to updates to our technology we've refined the idea of 'cortical columns' into a class which doesn't have useful explanatory power ('hypercolumns') and one which does ('minicolumns'.) The vertical integration of processing across layers of cortex by a collection of neurons is IMO of significant interest and import. You may disagree, but please don't pretend that these structures don't exist.
specialist 5y ago
> ...doesn't deny the common structure of cortical columns, but posits that they don't have a known function. Listening to an interview w/ Jeff Hawkins for "A Thousand Brains", it reminded me of Lingua Ex Machina [2009]. "A neuroscientist and a linguist show how evolution could have given rise to structured language." https://mitpress.mit.edu/books/lingua-ex-machina https://mitpress.mit.edu/books/lingua-ex-machina https://www.amazon.com/Lingua-Machina-Reconciling-Darwin-Chomsky/dp/0262531984 https://www.amazon.com/Lingua-Machina-Reconciling-Darwin-Cho... I tried to dig a bit, to see if there's a connection between Jeff Hawkins and William Calvin's works. No joy. I'm probably just grasping at straws. Am just a curious layperson. It's been ages since I read On Intelligence and Lingua Ex Machina. At the time, just the notion of Darwinian processes happening within the brain rocked my world.